1. Field of the Invention
The present invention relates to a boiler having enhanced heating efficiency and enabling simultaneous use of heating and hot water and, in more particular, to a boiler having enhanced heating efficiency and enabling simultaneous use of heating and hot water, which can supply sufficient heating-water even if heating equipment has a small heating surface area to enhance heating efficiency and can utilize simultaneously heating and hot water in light of a heating load and hot water load.
2. Description of the Related Art
In general, a heating dedicated boiler is a heating device which heats heating-water to a determined temperature utilizing combustion heat generated when fuel is burned, and supplies heating-water to a place in need of heating.
As shown in FIG. 1, a conventional heating dedicated boiler includes a tank 10 in which heating-water is stored; a circulation pump 20 for circularly supplying heating-water stored in the tank 10 to a main heat exchanger 30; a burner 40 for burning fuel so as to transfer combustion heat to heating-water passing through the main heat exchanger 30; a combustion chamber 50 providing a combustion space of the burner 40; a heating-water connecting pipe 71 through which heating-water stored in the tank 10 is supplied to the main heat exchanger 30; a heating-water supply pipe 72 through which heating-water heated by a heat exchange in the main heat exchanger 30 is supplied to heating equipment 60; and a heating-water return pipe 73 through which heating water, which has transferred heat to the heating equipment 60 and has a fallen temperature, is returned to the tank 10.
The conventional boiler constructed as above has the problem in that, if the heating equipment 60 has a small heating surface area, a supply amount of heating-water is limited so that a sufficient heating is not obtained by utilizing this heating equipment 60.
In other words, the conventional boiler has the problem in that, due to the structure in which heating-water heated in the main heat exchanger 30 is directly supplied to the heating equipment 60 through the heating-water supply pipe 72, an amount of heating-water supplied to the heating equipment 60 is limited to an amount of heating-water passing through the main heat exchanger 30 and then supplied to the heating equipment, and so in a case in which the heating equipment 60 has a small heating surface area, a supply amount of heating-water supplied to the heating equipment 60 is limited and, as a result, a heating is not done properly.
In the conventional boiler, therefore, in order that heating-water, whose supply amount is limited, transfers heat while passing through the heating equipment 60 to perform the heating properly, the heating equipment 60 should have a sufficiently large heating surface area. In the ondol heating (Korean floor heating system), for example, a piping of heating having a large heating surface area should be provided on an ondol floor. In a case in which the heating equipment 60 has a large heating surface area as above, a pressure loss of heating-water is also increased so that an efficiency of the boiler is lowered.
Meanwhile, depending on the heating surface area of the heating equipment 60, a supply temperature of heating-water supplied to the heating equipment 60 and a return temperature of heating-water which is returned after passing through the heating equipment 60 are determined. For example, if a high-capacity radiator having a large heating surface area as the heating equipment 60 performs the heating, the supply temperature of heating-water is set to 80° C. and the return temperature of heating-water is set to 60° C., and the heating is performed in the heating equipment 60 in response to the temperature difference of 20° C. between the supply temperature of heating-water and the return temperature of heating-water. If a small-capacity radiator having a small heating surface area as the heating equipment 60 performs the heating, the supply temperature of heating-water is set to 80° C. and the return temperature of heating-water is set to 70° C., and the heating is performed in the heating equipment 60 in response to the temperature difference of 10° C. between the supply temperature of heating-water and the return temperature of heating-water. As compared with the heating performed by utilizing the high-capacity radiator, therefore, in a case in which the heating is performed by utilizing a small-capacity radiator, a supply amount of heating-water, which is twice that for the high-capacity radiator, is necessarily required to perform the heating at the level which is the same as that of the heating performed by the high-capacity radiator.
However, in a case in which the heating equipment 60 has a small heating surface area, since a great quantity of heating-water which is circulated is required in order that the heating is performed at the level which is equal to that of the heating performed by the heating equipment having a large heating surface area, an amount of heating-water passing through the main heat exchanger 30 is also increased so that an element such as a heat transfer pin and the like provided in the main heat exchanger 30 for a heat transfer is eroded and corroded by an excessive amount of heating-water to deteriorate durability of and to reduce a service life of the main heat exchanger 30. In addition, since capacity of the circulation pump 20 provided in the boiler should be increased so as to supply a great quantity of heating-water to the main heat exchanger 30, an entire volume and weight of the boiler are increased and a great expense is required for manufacturing the boiler.